1. Field of the Invention
The present invention relates to an automatic focusing device of a camera which accurately adjusts focus in a short time on the basis of recent information and any piece of past information of intermittently calculated focus detecting information created in accordance with a focused object.
2. Related Background Art
Automatic focusing devices have hitherto been known in which the position of an object is predicted on the basis of recent and previous information of intermittently calculated focus detecting information on the distance between a photographic lens and the object. The lens is driven in accordance with the predicted position.
Because the focus detector makes an allowance for error, when the position of the object is predicted on the basis of recent and previous information, error in detecting focus is amplified, thus causing a deviation between the predicted and actual positions of the object.
To minimize the effect caused by such error, automatic focusing devices of cameras have been proposed in which all information on the detection of focus is statistically processed to predict the position of an object in motion.
Such an automatic focusing device, however, has a drawback in that a complicated calculation process is required for the statistical process, thus prolonging time for calculation.